The present invention pertains generally to vehicles such as cars, trucks, vans, and the like, and more particularly to a brake early warning system which alerts others that the vehicle is braking, and does so before the driver""s foot is actually applied to the brake pedal.
All motor vehicles are equipped with brake lights which indicate that the brake pedal has been depressed, and therefore that the vehicle is braking. The brake lights serve to warn a following motorist that the vehicle is braking, and that the following driver should also in turn commence slowdown or braking. Unfortunately, when the rear car is following too close considering the speed of both vehicles, the activation of the brake lights comes too late to avoid an accident. Various prior art inventions have addressed this problem. For example, U.S. Pat. No. 5,442,333 shows an urgent braking device which connects in series with a brake light system of a vehicle. The device incorporates power modulating means connected in parallel with an inertial switch. The device is attached to the vehicle with the inertial switch in an orientation relative to the vehicle whereby the switch is normally closed. The switch opens when the vehicle is decelerating in excess of a predetermined rate. Upon opening, the switch interrupts power supplied to the brake light system and a power modulating means is activated, resulting in a modulated power signal supplied to the brake light system causing the brake lights to flash. U.S. Pat. No. 5,463,258 illustrates a steering wheel 12 which incorporates an air bag unit 22. The air bag unit has a cover door 30 with a transducer 38 molded in a deformable front wall 35 of the cover door. The transducer can be a force sensitive resistor 38 which is operably connected to an electrical circuit 42 that actuates a horn 44 when the circuit senses a change in the resistance of force sensitive resistor 38. The force sensitive resistor 38 produces a suitable change in resistance when hand pressure is exerted on the front wall 35. U.S. Pat. No. 5,874,892 defines a vehicle warning system for vehicles comprising a pressure activated switch disposed within the steering wheel for activating a transmitter when more than normal pressure is applied to the steering wheel. The vehicle warning system further comprises a warning unit which contains a receiver, a sound generator, and warning lights. When a driver is faced with a potentially dangerous situation and instinctively grips the steering wheel harder, this causes the vehicle warning system to transmit of signals to the receiver in the warning unit of the initiating vehicle as well as the receivers in the warning units of other vehicles within a predetermined distance. The transmitted signal causes the warning light to flash and warning sound to be generated from the warning unit in each of the vehicles receiving the transmitted signal. U.S. Pat. No. 5,969,434 discloses a circuit for activating automobile brake lights. The circuit includes a battery, rear lights, horn, horn switch, center brake light flasher, brake pedal switch, and dash indicator light. When the horn in activated, the brake lights come on. When the enter brake light flasher is activated, the middle brake light comes on. When the brakes are activated, the dash indicator light comes on.
The present invention is directed to a brake early warning system which provides an early alert to others that a vehicle is in the process of braking. When a driver senses an urgent need to brake, the driver will instinctively brace, and in so doing will push against the steering wheel. The pressure exerted by the driver will deflect certain components of the steering column assembly. In the present invention this deflection is sensed by a movement sensor, which senses the relative movement between steering column assembly components. The movement sensor then sends a signal to activate the vehicle""s brake lights, and in a preferred embodiment, also the horn and headlights.
The bracing of the driver against the steering wheel occurs about 0.6 seconds before the driver depresses the brake pedal. Therefore, the present invention provides an increased margin of safety, particularly when the vehicle is travelling at higher speeds. The present invention can also alert others when a driver has slumped over the wheel, such as might be the case during sickness, a heart attack, or when asleep at the wheel.
The present invention can be enabled by the ignition system, so that it will not be active as the driver grasps the steering wheel while entering and exiting the vehicle. Also, the present invention can be utilized to alert tailgaters that they are following too close. In such situations, rather than stepping on the brake, the driver can simply push against the steering wheel to activate the brake lights.
In accordance with a preferred embodiment of the invention, a vehicle has (1) a steering column assembly having a plurality of components, and (2) a vehicle broadcast system which includes brake lights, a horn, and headlights. A brake early warning system includes a movement sensor which is connected to the steering column assembly. The movement sensor senses relative movement between two of the steering column assembly components, so that when the movement sensor senses relative movement, a signal is generated which activates the vehicle broadcast system.
In accordance with an important aspect of the invention, the steering column assembly components including a steering shaft, a steering column tube, and a steering assembly, and the movement sensor senses relative movement between two of these components.
In accordance with an important feature of the invention, the movement sensor includes a mechanical switch.
In accordance with another important aspect of the invention, the movement sensor senses movement when a driver pushes upon the steering wheel and thereby deflects certain of the steering column assembly components.
In accordance with another important feature of the invention, when the movement sensor senses movement, it deactivates the vehicle""s cruise control system.
Other features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.